Jewelers Vigilance Committee  (JVC)   A member organization dealing with legal issues pertaining to the Jewelry industry.
http://www.jvclegal.org


Gemological  Institute of America:   The leading educational facility in the United States for gemology and diamond evaluation and grading.  Most disputes require documentation provided by graduates of the GIA. 
http://www.GIA.edu
 
For Accurate Independent Jewelry and Gemological evaluations in Southwest Florida
www.JewelryAppraisersFla.com

Carigem    Over fifteen years operating as a gemological lab, teaching facility and appraisal organization operating within the most robust jewelry market in the western hemisphere.  Any items purchased within the duty free shops of the Caribbean, Mexico, South Florida or Alaskan market can get an accurate evaluation from Carigem.
www.Carigem.org


An interesting site filled with facts about coolored gemstones
http://www.Gemstone.org